the potx file is open then the dialog gets hidden behind it
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strPPTFile = Application.GetOpenFilename("PowerPoint Files (*.potx), *.potx")
oPPTApp.Visible = msoTrue
Set oPPTFile = oPPTApp.Presentations.Open(strPPTFile)
Set oPPTFile = oPPTApp.ActivePresentation
oPPTFile.SaveAs Application.GetSaveAsFilename(fileFilter:="PowerPoint((*.pptx),*.pptx")
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strPPTFile = Application.GetOpenFilename("PowerPoint Files (*.potx), *.potx")
oPPTApp.Visible = msoTrue
Set oPPTFile = oPPTApp.Presentations.Open(strPPTFile)
Set oPPTFile = oPPTApp.ActivePresentation
oPPTFile.SaveAs Application.GetSaveAsFilename(fileFilter:="PowerPoint((*.pptx),*.pptx")
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